element-plus/packages/components/countdown/src/utils.ts

import { isNumber } from '@element-plus/utils'

import type { Dayjs } from 'dayjs'

const timeUnits = [
  ['Y', 1000 * 60 * 60 * 24 * 365], // years
  ['M', 1000 * 60 * 60 * 24 * 30], // months
  ['D', 1000 * 60 * 60 * 24], // days
  ['H', 1000 * 60 * 60], // hours
  ['m', 1000 * 60], // minutes
  ['s', 1000], // seconds
  ['S', 1], // million seconds
] as const

export const getTime = (value: number | Dayjs) => {
  return isNumber(value) ? new Date(value).getTime() : value.valueOf()
}

export const formatTime = (timestamp: number, format: string) => {
  let timeLeft = timestamp
  const escapeRegex = /\[([^\]]*)]/g

  const replacedText = timeUnits.reduce((current, [name, unit]) => {
    const replaceRegex = new RegExp(`${name}+(?![^\\[\\]]*\\])`, 'g')
    if (replaceRegex.test(current)) {
      const value = Math.floor(timeLeft / unit)
      timeLeft -= value * unit
      return current.replace(replaceRegex, (match) =>
        String(value).padStart(match.length, '0')
      )
    }
    return current
  }, format)

  return replacedText.replace(escapeRegex, '$1')
}